CONTENTS List of tables viii Preface ix Acknowledgements xi Part 1. The Technical Background 1. Describing light 3 Flow and itensity 3 Illuminance and luminance 4 All the units are related 5 Reflection and transmission 6 2. Describing colour 9 Surface colours 9 Coloured lights and chromaticity 1 2 3. Seeing light and colour 1 5 Adaptation 15 Central and peripheral vision16 Wavelength, brightness and colour 1 7 Mixtures and constancy 18 Some non-visual effects of light 19 4. Light from electricity 21 Incandescent lamps - the heated filament 21 Discharge lamps - the glowing gas 23 Which lamp? 26 Controlling the light 28 5. Sun and sky 31 Where is the sun? 31 How often does the sun shine? 34 Illuminance from sunlight and skylight 34 Daylight in a room 36 Daylight factors 37 Part 2. Designing 6. Information, control and energy 39 Lighting and information 41 Lighting and control 44 Lighting and energy 45 Interrelationships 46 7. Lighting and room character 47 Associations 48 In a cave or on a cloud? 49 Uniform or glittering? 53 Surfaces : brightness and lightness 56 Familiar or unexpected? 57 8. The dimensions of colour59 A hierarchy of dimensions 59 Colour, lighting and shape 61 Lamp colour and surface colour 62 9. Task lighting 65 Illuminance on the task 65 Contrast within the task 68 Contrast between the task and its surroundings 70 Discomfort glare 72 In conclusion 73 10. View and daylight 75 People like windows 75 Diffuse brightness 78 Task lighting 79 Sunlight 80 Redirecting daylighting devices 82 Clare and complexity 83 Daylight with electric lighting 84 11. Display 87 The principle of contrast 87 Display lighting techniques 89 Museums and galleries 94 12. The exterior of buildings99 Functional requirements 99 Luminance, illuminance and colour 100 Buildings and facades 103 Pedestrian routes and surrounding areas 106 The overall view 107 Daytime appearance, energy efficiency and maintenance 108 13. Emergency lighting 109 Escape lighting 109 Shut-down lighting and standby lighting 110 Equipment and system design 110 14. Maintenance, energy and costs 113 Installation maintenance 114 Energy efficiency in lighting 117 Lighting costs : capital and operational 120 Part 3. Calculations 15. What calculations are for 123 Use and accuracy 125 Standards and data 126 16. Examples 129 (a) Vertical sky component and site layout 130 (b) Sunlight availability133 (c) Average daylight factor: planning for daylight 135 Id) The lumen method : general room lighting139 (e) Estimating energy use 143 (f) The point source formula : direct illuminance from a small luminaire 145 (g) Accent lighting : which spotlight? 148 (h) Walls and ceilings 152 (i) Data 156 (j) References and further reading 162 Index 163